Do you have an Anycubic Kobra 2 Pro/Plus/Max 3D printer? Did you know it has a security vulnerability?
If you answered "yes" to both those questions, then chances are that I can guess just how you found out your 3D printer was vulnerable to hackers.
My bet is that you might have learnt about the problem after seeing a strange message displayed on your device, claiming that it had been hacked.